Spark plug



July 2a, 193s.. P MIRON www@ SPARK PLUG Filed Aug. 14, 1953 Patented July 28, 1936 f UNITED Pl v, .SPARK PUIG# Y Y PhnippeMii-on, saint Buruma-Manitoba, v Canada f5.' ,f Applicatio'llugust`-14, 19st, serial No."tsaess s claims.' (015123-169) l' My invention relates to improvements in spark plugs such as are commonly used` for igniting a charge in an internal combustion engine and par- 5 ticularly to improvements in the sparking ele-- ments and associated parts.

One of the objects of my invention is to proof explosion fluids and discharge of the productsy of combustion, said chamber being designedto maintain the-plug free of carbon with consequent improved operation of the sparkingelements, and also to assist in heating the sparkplug when starting a cold engine so that it will warm up faster.

Other objects of my invention will become apr-j. parent from the accompanying description taken. in conjunction with the drawing wherein like characters of reference indicate like parts throughout the diiierentviews and whereini Fig. 1 is a perspective side view of the spark plug assembled.

Fig. 2 is a view in vertical section of a. spark plug embodying my improvements.

Fig. 3 is an inverted plan view thereof.

Fig. 4 is a fragmentary view, partly broken away and partly sectioned, of the lower end of a plug embodying my improvements but including a separable ball chamber.

Fig. 5 is a sectional View of a separable ball chamber of an extension type for use in certain types of engines.

Fig. 6 is a side view of a terminal connector.

Fig. 'I is a plan view of the connector.

While I have shown only the preferred forms of my invention, I wish it understood that various changes or modifications may be made within the scope of the claims hereto attached Without departing from the spirit of the invention.

Having reference to the drawing, my improved spark plug includes an outer metallic shell I threaded at its lower end as indicated at 2 adapted to be screwed into the registering perforation in the cylinder of an internal combustion engine and a centre power electrode rod 3 in a petticoat type core 4 made of insulating material, preferably porcelain, and a gland nut 5 threadably engaging the top of the outer shell as indicated at 6, the outer shell, 'core and gland nut are providedwith cooperating, gasket seats in which. asbestos lined gasket'stand' 9 are interposed.` Threadedfon the upper end of the power electrode4 is an end cap I0 with packing lli betweenthe core and endcap suitably seated in the core, aterminal cap Il being provided for attachmentlof the high tension wire.

The lower end of the electrode rod is secured by a collar l2 Xed thereto, said 4collar being l0 seatedin the recess l3.formed in the core 3, the lowerend of the electrode rod 3 terminating level with, or justshort vofthe lower end of the core 3.

The lower portion ofthe outer shell l provides a cage or chamberll with one or more apertures l5 |5.-'I5 for admission of gases from the .combustion chamber and within which ls moveable a ball I6 ofconduc'tive material, the ball, thecharnber andfthe centre electrode being preferably made of. ignition alloy. s

The outer shell 2 Ywhich is grounded to the engine andfthe centre electrode rodv 3 form the two electrodes'of a circuit including, a source of power, thehigfh `tension wire connecting the upper end of the electrode rod and the source of power. The ball I6 being interposedbetween the electrodes la'vesafgap betweenon'elor other of the electrodes andthe ball across which a spark is caused to jmnp when la "high voltagecurrent is passed through the circuit.

In order to maintain a uniform sparking relation, it is necessary that the chamber i4 be formed to restrict movement of the ball i6 within certain dened limits designed to maintain a uniform spark gap. The said chamber has its side wall Il ared slightly outward from its lower end and the outer portion of the bottom I8 directed downward with the central portion of the bottom, immediately beneath the centre electrode rod, horizontal leaving a slight depression in the centre of the bottom portion, formed by a relatively ilat center section 35 with surrounding downwardly inclined annular section 36. The side wall l is of circular formation, upstanding relative to the section 36, said wall being inclined outwardly relative to the plane of the center section 35 of the bottom section, with transverse fluid passages provided by the apertures |5-l5.

By this formation of the ball chamber the 50 mately 18 from the vertical and the outer por- 55 The core 4 is formed recessed to provide` anr annular combustion chamber I9 communicating by an annular passage 20 with the ball chamber i I4 and thence, through the openings I5 in theA bottom of said chamber, with the engine'cyl#V inder within which the spark plug isi/mounted@ the number of said openings I5 varying in accordance with the size of the plug. Explosion fluids under pressure enter the chamber I9` through the openings I5 and passage 2U and by,

being ignited therein serve to eliminate carbon Vfrom the sparking elements as a result ofthe explosive force and re applied to said elements.

Any carbon remaining will be drawn out on the intake or suction stroke rendering the spark' plug self cleaning. In addition thev initialv explosion within said chamber in starting an engine serves to warm the spark plug and facilitate sub-A` sequent explosions. The core includes a tipA or end portion 33 of elongated `cylindrical formation adapted for co-operation with a section 34 of the shell I, said section and core end portion extending in parallel relationship defining the passage 20 of relatively narrow elongated formation.

In Figure 4 is shown a spark plug embodying my improved ball chamber but in a separable form. In this showing2l indicates the shell, 22

the core, and 23 the power electrode. Threaded into the shell 2I is an end section 24 providing a ball chamber 25 with ball electrode -26. For adjustment of the connection of said endV section 25 with the shell 2I a shim 21 is insertablethere-A between permitting variation of the spark gap;

In other respects the formation and operation of the sparking elements remains the same.

Fig. 5 shows a separable ball chamber lof airr elongated character for use in certain types of' engines, such as certain tractors; where itiis necessary for the sparking elements to be lower 'in' the combustion chamber owing to peculiarities in formation of the cylinder head.

Figures 6 and 7 disclose an improved terminal connector for the plug which includes a tubular body 28 attachable to a supply cable and having an integral plate 29 with opening 30 engageable over the end portion of the power electrode terminal cap, said opening having a slotted extension 3 I: for. engagement of said terminal cap. On theplate-,ZS is asp'ring 32 engageable to lock the connector on to the terminal cap.

1 .,:It is understood that certain features of the devlceare useful without reference to other fea- *ture'snd the use of such individual features iS -conte,1I1p1aI42c l .:bythis invention and is within the :scope of the appended claims.

,Having claim'i`s` l, A;;spark plug comprising a core having an elongated tip portionand an annular recess spaced froxnithev end ythereof by said'tip portion, and ashell housing said core, wherein said shell r,thus, Ad'escribed my invention, what I and* tip portionv'extend inr substantially parallel relationship' spaced apart forming a relatively narrow elongated passage communicating with the recess inthev core.' l

. 2. A spark plug comprising a coreY having any" annular recess formed-therein spaced from the' lower end thereof defining an elongated encl` portion and a shell housingvsaid core, wherein the core end-portion-is'of substantiallylcylin# drical formation and the shell includes a section extending in-parallel relationship with said end portion spaced `therefrom to form a relatively narrow elongatedl passage communicating with the recessinthe core. Y' f 3. A spark plug comprising a core and a shell housing said core, saidishell including a sparking chamber adapted'for reception of a movable elementfsaidchamber including a bottom por-j tion having a-relatively hat center sectionand a downwardlyinclined annular section surround? ingthefcente'r section, and a circular upstanding wall,` said wall being inclined outwardly relative to' theA plane ofthe center ofthe bottom section, s

the bottom section' being further formed with transverse; fluid passages. Y y

" yPHILIPPE MIRON. 

